@dethduck
I find it more likelly that he is a cyborg of some kind thats not native to this world.
the last line can be taken as a hint off him not being human, or that he suspects her of suspecting him.
A normal person dont survive killing themselfs after all, and i find it hard to belive he "escaped" from the last chapter.
So i come to the conclusion that it's a different person trying look like him, or the more likely reason considering the technology he have....
Its a copy of him made by the nanomachines making him a cyborg or robot.